According to mcclelland's need theory, the is interpersonal because it involves influence over other people.

The Need for Power.

People that have a need for power want to influence and control others. A person's need for power can be one of two types: personal and institutional. Personal power is the need to direct others for the sake of directing others. Personal power expressions are often viewed as outspoken, forceful and demanding. Persons who need Institutional power want to organize the efforts of others to further the goals of the organization.  

it depends on which society you are referring to. many civilization performed rituals so the gods would with their growing season but the most well known is that of the aztecs. they would make sacrifices, usually animals, but sometimes humans as well.

answer; no longer than a reasonable period of time;